my $grocerylist = {
    Eggs      => '1.99',
    Milk      => '1.75',
    Cookies   => '2.99',
    Carrots   => '1.25',
    Eggplant  => '1.89',
    Cereal    => '3.25',
    Gum       => '0.75',
    Juice     => '1.99'
};

my $cart = { 
    items => {},
    total => 0,
    cash  => 0,
};

print "Welcome to the Acme(tm) grocery store.\n";
print "How much do you have to spend today? ";
chomp ($cart->{cash} = <STDIN>);
printf "You have: \$%.2f\n", $cart->{cash};

while ( ( $cart->{cash} - $cart->{total} ) > 0) {

    my $action = menu();

    if ( $action eq 'Q') {
        quit($cart);
    }
    elsif ($action eq 'Showall' ) {
        showall($grocerylist);
    }
    elsif ($action eq 'Cart'){
        cart($cart);
    }
    elsif (exists $grocerylist->{$action}){
        add_cart( $cart, $grocerylist, $action );
    }
    else {
        print "\n*****Don't know how to do $action\n\n";
    }
}

sub add_cart {
    my ( $cart, $grocerylist, $item ) = @_;
    if ( ($cart->{total} + $grocerylist->{$item}) > $cart->{cash} ) {
        printf "\nSorry you can't afford '%s' @ \$%.2f as you only have \$%.2f\n",
            $item, $grocerylist->{$item}, $cart->{cash}-$cart->{total};
    }
    else {
        $cart->{items}->{$item}++;
        $cart->{total} += $grocerylist->{$item};
        print "\nAdded $item to cart OK\n";
    }
}

sub menu {
    print qq!
Enter:
    item name, 
    'cart' to view your current purchases,
    'showall' to show all available items.
    'q' to quit and display purchases.
Action: !;
    chomp (my $action = <STDIN>);
    $action = ucfirst(lc $action);
  return $action;
}

sub quit {
    my $cart = shift;
    checkout($cart);
}

sub cart {
    my $cart = shift;
    print "This is Cart so far:\n\n";
    printf("%-15s %s\n" .('-'x25) ."\n", "Item", "Quantity");
    printf ("%-15s %s\n", $_, $cart->{items}->{$_}) for keys %{$cart->{items}};
    printf "
Spent      \$%.2f
Budget:    \$%.2f
Remaining: \$%.2f\n",
    $cart->{total}, $cart->{cash}, $cart->{cash} - $cart->{total};
}

sub showall {
    my $grocerylist = shift;
    printf("%-15s %s\n" . ('-'x25) ."\n", 'Item', 'Price');
    printf("%-15s %s\n", $_, $grocerylist->{$_}) for keys %$grocerylist;
}

sub checkout {
    my $cart = shift;
    require Data::Dumper;
    print Data::Dumper::Dumper($cart);
    exit 0;
}